Focus turns to Building Grass for the Autumn

John Greaney, Dairy Advisor on the Teagasc/Aurivo Joint Programme turns his focus to Building Grass for the Autumn as he outlines Autumn grazing targets and gives advice for high and lower stocked farms. John emphasises the importance of grass measuring and having a plan. Read more here
Normal service has resumed as discussion groups make up for lost time due to restrictions earlier in the spring. Whispers at group meetings suggested farmers across the north-west were eager for rain. Thankfully, the rain has arrived and coincides well with building grass covers on farms to extend the grazing season into the back end.
Irrespective of what has happened to date in terms of growth, it is now time to start building grass for the autumn. Growth has once again surpassed demand making it slightly easier for farmers to build a reserve of grass before growth drastically slows down in October. Targets and how early one should start building covers varies depending on stocking rate and land type. The aim should be to keep cows at grass for as long as possible but every farm is different.
The easiest way to build up grass is to simply extend the rotation length. Throughout the main grazing season farmers would consistently target grazing covers at 1400kgDM/ha. However, as the grazing season progresses and we try to add days to each rotation length pre grazing covers may increase slightly. For example a cover of 1650kgDM/ha a few weeks ago would have been skipped over for silage, but if you are building covers you’d graze it.
Highly Stocked Farms
A rough rule of thumb is to target an Average Farm Cover (AFC) of 1,000kgDM/ha or 300- 330kgDM/cow by September 1st but stocking rate ultimately dictates everything. Farms carrying higher stocking rates should be mindful not to let AFC peak above 1200kgDM/ha as pre-grazing covers will go too strong becoming too difficult to graze out especially if the weather breaks. These paddocks will also recover a lot slower. Higher stocked farms are harder managed in the shoulders of the year particularly where not all the farm is available to graze. The differential between growth and demand will be a lot less so introducing more supplement is often necessary to reduce demand. All farmers should have a plan and the first step of any plan should be to get all the farm available for grazing. Any paddocks previously held for silage should be taken out immediately. Unless the stocking rate on the farm is very low, reseeding shouldn’t be carried out at this stage.
Lower Stocked Farms
Farms stocked below 3.0lu/ha shouldn’t need to start building grass until after mid-August, targeting a cover/Lu of 180-200kg/ha. Any farmer stocked at 2.5lu/ha or less will be building grass into mid-October on the average year as carrying too much grass into the backend could be detrimental to the quality of the sward next spring.
Pasturebase
As the main grazing season comes to an end farmers often decide to cut back on the number of grass walks and figures inputted into Pasturebase tend to slow. To keep on track and ensure a healthy bank of grass is present on the farm measuring is paramount. The budgeting tool gives farmers’ confidence to make decisions quickly.
In summary
There are two objectives farmers need to achieve over the next month in terms of autumn grazing management of dairy cows. Firstly the cows must be adequately fed using the cheapest available feed which is grazed grass. The second objective is to set the farm up for spring grazing, which is more valuable than autumn grass. Many farmers do not realise that the grazing season begins in the autumn and that autumn management of grazed grass is the primary factor influencing the supply of grass available in spring on any farm. Putting a plan in place and more importantly sticking to it will ensure cows remain at grass well into the backend and there’s plenty of grass on the farm next spring.
Autumn Grazing Targets
For more on the topic of grassland see Grassland
Teagasc Advisors are regular contrbutors of articles on topics of interest to farmers here on Teagasc Daily To learn more about discussion groups or grassland management contact any of our Teagasc offices using this link Teagasc Advisory Regions here